COVID-19 Resource Center

COVID-19 Resource Center

Source: News Release.
Disclosures: Fauci reports no relevant financial disclosures.
March 31, 2021
1 min read

Study participants begin receiving Moderna’s variant-specific COVID-19 vaccine

Source: News Release.
Disclosures: Fauci reports no relevant financial disclosures.
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The NIH on Wednesday announced the start of a phase 1 clinical trial evaluating Moderna’s variant-specific COVID-19 vaccine, saying the shot has been administered to trial participants.

Moderna shipped doses of the vaccine — a modified version of its mRNA-1273 vaccine, which has been authorized for use in the U.S. since December — to the NIH last month for testing. The vaccine was tweaked to target the B.1.351 variant, which was first identified in South Africa.

 Source: Adobe Stock
The NIH said a trial has begun evaluating Moderna’s variant-specific COVID-19 vaccine. Source: Adobe Stock.

According to the NIH, the new trial will enroll 210 healthy adults at four clinical research sites in Atlanta, Cincinnati, Nashville and Seattle. Investigators at the four sites anticipate that the trial will be fully enrolled by the end of April, the NIH said.

The modified vaccine will be studied in both vaccinated and unvaccinated adults. The vaccinated adults already received mRNA-1273 last year as part of a clinical trial. They will be randomly assigned to receive either a single booster vaccination of 50 µg of the modified vaccine, mRNA-1273.351, or a single vaccination containing one 25 µg dose of mRNA-1273 and one 25 µg dose of mRNA-1273.351.

A separate clinical trial will assess a booster shot of the original vaccine in the remaining vaccinated study participants.

According to National Institute of Allergy and Infectious Diseases Director Anthony S. Fauci, MD, the B.1.351 variant has been detected in at least nine U.S. states. The NIAID, which co-developed the vaccine with Moderna, is leading and funding the new trial.

Anthony S. Fauci

“Preliminary data show that the COVID-19 vaccines currently available in the United States should provide an adequate degree of protection against SARS-CoV-2 variants,” Fauci said in the NIH release. “However, out of an abundance of caution, NIAID has continued its partnership with Moderna to evaluate this variant vaccine candidate should there be a need for an updated vaccine.”